WINPRO - Clinical trial • Breast Cancer Foundation NZ

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Early Breast Cancer clinical trials for ER+

Updated: February 9, 2021

An open-label, randomized, window of opportunity study between diagnosis and definite surgery, to assess the effect of antiestrogen therapies, alone and in combination with microionized progesterone (prometrium) in patients with newly diagnosed ER+PR+ breast cancer.

This study is examining a combination of hormone treatments that may be useful as a pre-surgery treatment for breast cancer. The main aim of the study is to assess the effects of endocrine therapy with or without prometrium on paired pre and post-treated breast cancer tissue for cell proliferation (which is measured by the tumoral Ki67 expression). The hypothesis is that the combination of endocrine therapy with prometrium will result in a significant reduction in cell proliferation (primary endpoint) when compared to endocrine therapy alone.

Who is it for?

You may be eligible for this study if you are female, post-menopausal and have histologically confirmed newly diagnosed hormone receptor-positive breast cancer.

Study details

Participants in this study will be randomised (by chance) to one of three groups. One group will receive the medications letrozole and prometrium, another group will receive the medications tamoxifen and prometrium, and the other group will receive the medication letrozole alone. The assigned treatments will be taken daily for two weeks prior to surgery. Participants will provide blood samples and consent to their cancer tissue being used for analysis, in addition to a medical examination.

It is hoped this research will provide fundamental evidence of the efficacy and safety of these medications in patients with early-stage breast cancer

Full trial information


Calvary North Adelaide Hospital, Adelaide
Royal Melbourne Hospital, Melbourne
Campbelltown Hospital, Sydney
Royal Prince Alfred Hospital, Sydney
St Vincent's Hospital, Sydney
Sydney Adventist Hospital, Sydney


Claire Gray

If you think you might be a candidate for this trial, use the contact details supplied, or talk to your doctor.

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